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Terpenes: what they are and whether they matter

Terpenes are the aromatic compounds that give cannabis its smell. Claims that they shape or boost the effects of CBD rest on laboratory work, not human trials.

Facts checked 13 November 20265 min readHow we research

Terpenes are the aromatic compounds that give cannabis its smell and flavour.1 They are often promoted as active ingredients that shape or boost the effects of CBD. That claim rests on laboratory work. Receptor studies have mostly been negative, and no human trial has shown that terpenes in a CBD product change any health outcome.23

What are terpenes?

Terpenes are a very large family of natural compounds. They are the biggest single group of chemicals in the cannabis plant, with more than 100 identified.1

They are not unique to cannabis. The same molecules give many familiar plants their scent:1

Terpene Also found in
Myrcene Hops
Limonene Citrus oils
Linalool Lavender
Beta-caryophyllene Black pepper

Other common cannabis terpenes include alpha-pinene, beta-pinene, terpinolene and humulene.1

In cannabis, terpenes are made mainly in the same resin glands on the flowers that make cannabinoids.1 They are a separate chemical family from cannabinoids such as CBD and THC. See the cannabis plant.

How much is in the plant?

Not a great deal. In one set of measurements, the lighter terpenes (monoterpenes) made up 3.1 to 28.3 milligrams per gram of dried flower, which is 0.3% to 2.8% by weight. The heavier ones (sesquiterpenes) made up 0.5 to 10.1 milligrams per gram.1

The amount in a finished CBD product depends on how it was made. A CBD isolate contains none. Full-spectrum and broad-spectrum extracts keep some. See full spectrum vs broad spectrum vs isolate and how CBD is extracted and made.

What is claimed about terpenes?

Three claims are common:

  1. Each terpene has its own effect (myrcene is “sedating”, limonene is “uplifting”, and so on).
  2. Terpenes work together with cannabinoids to make an extract more effective than pure CBD. This is part of the entourage effect.
  3. A product’s terpene profile predicts how it will make you feel.

These ideas are plausible enough to be worth testing. Terpenes are fat-soluble and cross easily into the brain.1 The question is what happens when they are tested.

What does the research show?

Terpenes do not appear to act on cannabinoid receptors. In a 2019 laboratory study, six common cannabis terpenes did not activate the CB1 or CB2 receptors and did not change how THC signalled through them.2

A 2020 study tested myrcene, alpha-pinene, beta-pinene, beta-caryophyllene and limonene, alone and in mixtures. None altered the way THC or CBD bound to or activated the receptors. The only signal was weak binding of beta-caryophyllene at CB2. The paper’s title states the conclusion: “Terpenoids From Cannabis Do Not Mediate an Entourage Effect by Acting at Cannabinoid Receptors”.4

The same was found at other targets. A further study found terpenes did not change the actions of cannabinoids at two other receptors, TRPA1 and TRPV1.5

One study points the other way. A study in mice and in cells reported that some terpenes produced cannabinoid-like effects and added to the activity of a cannabinoid.6 Results in mice often fail to carry over to people, and the doses used in animals can be far above what a person would get from a product.

Other routes have not been ruled out. The authors of the 2020 study were careful to say their work “cannot rule out the existence of an entourage effect”. Terpenes might act on targets unrelated to cannabinoids, or simply through their smell.4

Human trials are missing. We found no randomised trial in people showing that adding terpenes to CBD improves a clinical outcome.

Do terpene profiles or “sativa” and “indica” labels predict effects?

There is no good evidence that they do. Terpenes are responsible for the differences in smell between cannabis varieties.1 But the everyday “sativa” and “indica” labels have been described by a botanist reviewing the plant’s classification as “almost meaningless” because the varieties have been so widely cross-bred.7 A smell is not a reliable guide to an effect.

Are terpenes safe?

The terpenes in cannabis are the same compounds found in many foods and herbs, as the table above shows.1 That says little about swallowing concentrated terpenes in an oil every day, or inhaling them, because those uses have not been studied in the same way as CBD itself. If a product lists added terpenes, treat that as an unstudied extra, not a proven benefit. General cautions are on CBD side effects.

What this means when you read a label

  • A terpene list tells you about smell and taste, and about how much of the original plant extract survived processing.
  • It does not tell you the product will work better, or differently, for any condition.
  • A certificate of analysis may include a terpene panel. The cannabinoid results (how much CBD, how much THC) and the contaminant tests matter far more.
  • The strongest evidence for CBD comes from a purified product that contains no terpenes at all.8

Footnotes

  1. Andre CM, Hausman JF, Guerriero G. Cannabis sativa: the plant of the thousand and one molecules. Frontiers in Plant Science, 2016. https://www.frontiersin.org/articles/10.3389/fpls.2016.00019/full ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8 ↩9

  2. Santiago M, et al. Absence of entourage: terpenoids commonly found in Cannabis sativa do not modulate the functional activity of THC at human CB1 and CB2 receptors. Cannabis and Cannabinoid Research, 2019. https://pubmed.ncbi.nlm.nih.gov/31559333/ ↩ ↩2

  3. Scoping review of the evidence for the cannabis entourage effect, 2023. https://pubmed.ncbi.nlm.nih.gov/37535820/ ↩

  4. Finlay DB, Sircombe KJ, Nimick M, Jones C, Glass M. Terpenoids from cannabis do not mediate an entourage effect by acting at cannabinoid receptors. Frontiers in Pharmacology, 2020. https://www.frontiersin.org/articles/10.3389/fphar.2020.00359/full ↩ ↩2

  5. Study of cannabis terpenes and cannabinoid actions at TRPA1 and TRPV1 channels. PubMed Central. https://pmc.ncbi.nlm.nih.gov/articles/PMC7759271/ ↩

  6. Study reporting that cannabis terpenes are cannabimimetic and enhance cannabinoid activity in mice and cells. PubMed Central. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8050080/ ↩

  7. McPartland JM. Cannabis systematics at the levels of family, genus, and species. Cannabis and Cannabinoid Research, 2018. https://pmc.ncbi.nlm.nih.gov/articles/PMC6225593/ ↩

  8. Epidiolex (cannabidiol) oral solution, United States prescribing information. DailyMed, National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8bf27097-4870-43fb-94f0-f3d0871d1eec ↩

Common questions

What do terpenes do in CBD oil?

They contribute smell and taste. Claims that they change or strengthen the effects of CBD come from laboratory and animal studies. No human trial has shown that terpenes in a CBD product improve a clinical outcome.

Are terpenes cannabinoids?

No. They are a separate family of compounds. Both are made in the same resin glands of the cannabis plant, but terpenes are found throughout the plant world, while cannabinoids such as CBD and THC are characteristic of cannabis.

Do terpenes get you high?

No evidence suggests so. In laboratory tests, common cannabis terpenes did not activate the CB1 receptor, which is the receptor THC acts on to cause a high.

Does CBD isolate contain terpenes?

No. An isolate is CBD on its own. Full-spectrum and broad-spectrum extracts keep some of the plant's terpenes, and some products have terpenes added back in.

This page is general information, not medical or legal advice. Laws and evidence change; we show the date we last checked the facts at the top of every page. Talk to your doctor or pharmacist before starting, stopping or changing any medicine.

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